Rosy, tiger, and cherry barbs are all compatible in a community tank, since they're all Cyprinids. Although tiger barbs can be nippy if kept in too small a group. Generally, cyprinids are fish that do best when kept in shoals/schools. Tell us how many fish of each kind you have in your tank, so that we know if it's overstocked or not. The general rule is to have 1 inch of fish per 1 gallon of water, but it's better for the fish to have 1 inch of fish per 2 gallons of water.
Your tank is not overstocked then. Although I don't know how large do tiger and rosy barbs grow, but probably not much larger than cherry barbs? I know that cherry barbs don't grow large (about 1.5 inches). When you buy fish, you have to take into account their adult size. If your fish seem fine together, just leave them as they are. You could not put into a 10 gallon tank more of each kind anyway. So just observe them as they grow together. They most likely will be fine (but I can't guarantee about the tigers). Well, this is what I think. It will be best if Gunnie or Butterfly here will tell you what they think. They're really knowledgeable.
well thank you for all the help you seem to be really nice. Tiger barbs maximum size is 2.5 inches and rosey barbs are about 2-6 inches. I have read that they grow to 2.5 or 6 inches but I don't know how big so I will ask and find some more info but thanks again for the info